Comments

I assume that you want to create that array in storage, then it is free (correction: it is not totally free, but the cost does not depend on the size). It is not free to fill it with non-zero values, though.Creating arrays in memory is not yet implemented.

The constructor is just too expensive and will not fit the block gas limit.As you are initialising all coin wallets in exactly the same way, you can change your logic tohandle uninitialised values (zero) as your default values and not store anything. This way, it will work.